package com.lins.framework.utils;

import android.content.Context;
import android.os.Environment;

import java.io.File;
import java.math.BigDecimal;

/**
 * 本应用数据清除管理器
 * 
 * @author Lins 2015-12-21
 */
public class DataCleanManager
{

    /**
     * 计算缓存文件大小
     * 
     * @param context
     * @return
     * @throws Exception
     */
    public static String getTotalCacheSize(Context context)
        throws Exception
    {
        long cacheSize = getFolderSize(context.getCacheDir());
        if(Environment.getExternalStorageState().equals(Environment.MEDIA_MOUNTED))
        {
            cacheSize += getFolderSize(context.getExternalCacheDir());
        }
        return getFormatSize(cacheSize);
    }

    /**
     * 清除缓存文件
     * 
     * @param context
     */
    public static void clearAllCache(Context context)
    {
        deleteDir(context.getCacheDir());
        if(Environment.getExternalStorageState().equals(Environment.MEDIA_MOUNTED))
        {
            deleteDir(context.getExternalCacheDir());
        }
    }

    private static boolean deleteDir(File dir)
    {
        if(dir!=null&&dir.isDirectory())
        {
            String[] children = dir.list();
            for(int i = 0; i<children.length; i++)
            {
                boolean success = deleteDir(new File(dir, children[i]));
                if(!success)
                {
                    return false;
                }
            }
        }
        return dir.delete();
    }

    // 获取文件
    // Context.getExternalFilesDir() --> SDCard/Android/data/你的应用的包名/files/
    // 目录，一般放一些长时间保存的数据
    // Context.getExternalCacheDir() -->
    // SDCard/Android/data/你的应用包名/cache/目录，一般存放临时缓存数据
    public static long getFolderSize(File file)
        throws Exception
    {
        long size = 0;
        try
        {
            File[] fileList = file.listFiles();
            for(int i = 0; i<fileList.length; i++)
            {
                // 如果下面还有文件
                if(fileList[i].isDirectory())
                {
                    size = size+getFolderSize(fileList[i]);
                }
                else
                {
                    size = size+fileList[i].length();
                }
            }
        }
        catch(Exception e)
        {
            e.printStackTrace();
        }
        return size;
    }

    /**
     * 格式化单位
     * 
     * @param size
     * @return
     */
    public static String getFormatSize(double size)
    {
        double kiloByte = size/1024;
        if(kiloByte<1)
        {
            return size+"Byte";
        }

        double megaByte = kiloByte/1024;
        if(megaByte<1)
        {
            BigDecimal result1 = new BigDecimal(Double.toString(kiloByte));
            return result1.setScale(2, BigDecimal.ROUND_HALF_UP).toPlainString()+"KB";
        }

        double gigaByte = megaByte/1024;
        if(gigaByte<1)
        {
            BigDecimal result2 = new BigDecimal(Double.toString(megaByte));
            return result2.setScale(2, BigDecimal.ROUND_HALF_UP).toPlainString()+"MB";
        }

        double teraBytes = gigaByte/1024;
        if(teraBytes<1)
        {
            BigDecimal result3 = new BigDecimal(Double.toString(gigaByte));
            return result3.setScale(2, BigDecimal.ROUND_HALF_UP).toPlainString()+"GB";
        }
        BigDecimal result4 = new BigDecimal(teraBytes);
        return result4.setScale(2, BigDecimal.ROUND_HALF_UP).toPlainString()+"TB";
    }

    public static String getCacheSize(File file)
        throws Exception
    {
        return getFormatSize(getFolderSize(file));
    }

}
